Methods to measure and predict the transfer function size dependence of individual DMAs
Methods to measure and predict the transfer function size dependence of individual DMAs
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DOI：
10.1016/s0021-8502(03)00020-x
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发表时间：
2003-05-01
影响因子：
4.5
通讯作者：
Martinsson, BG
中科院分区：
文献类型：
--
作者：
Karlsson, MNA;Martinsson, BG
在对维也纳型差分迁移率分析仪（DMA）副本的传递函数的这项研究中，发现三个本应相同的DMA在传递函数宽度方面表现出明显差异。这意味着为了从DMA测量中获得准确结果，需要逐个确定DMA的传递函数。在较宽的佩克莱特数范围（400 - 400000）内，通过实验研究了传递函数宽度的尺寸依赖性以及三个DMA的穿透率。三个DMA中的两个所表现出的传递函数宽度超过了扩散引起的展宽。假设除扩散展宽外还存在仪器特定的、与尺寸无关的展宽，那么所有三个DMA的宽度的尺寸依赖性都可以在百分之几的误差范围内得到解释。通过与圆形管中的沉积相关联来评估穿透率。实验数据与简单模型之间取得了极好的一致性。穿透率研究扩展到包括文献数据，表明该简单模型可以应用，并且不同类型的DMA之间存在明显差异。这项研究的结果表明，通过测量单个粒径的传递函数，可以估算传递函数宽度和穿透率的尺寸依赖性，从而大大减少了DMA用户表征其仪器所需的工作量。（C）2003爱思唯尔科学有限公司。保留所有权利。
In this study of the transfer function of copies of the Vienna-type differential mobility analyser (DMA) it was found that three, supposedly identical, DMAs exhibited distinct differences with respect to the width of the transfer function. This means that the transfer function of a DMA needs to be determined on an individual basis in order to obtain accurate results from DMA measurements. The size dependence of the transfer function width and the penetration of three DMAs were investigated experimentally in a broad range of Peclet numbers (400-400000). Two of the three DMAs exhibited transfer function widths in excess of the broadening induced by diffusion. The size dependence of the width of all three DMAs could be explained within a few percents by assuming an instrument-specific, size-independent broadening in addition to diffusion broadening. The penetration was evaluated by relating to deposition in a circular tube. Excellent agreement between the experimental data and the simple model was obtained. The penetration study was extended to include literature data, showing that the simple model could be applied and that there are distinct differences between different DMA types. The results of this study indicate that the size dependence of the width of the transfer function and the penetration can be estimated by measuring the transfer function for a single particle size, thus greatly reducing the amount of work required by DMA users to characterise their instruments. (C) 2003 Elsevier Science Ltd. All rights reserved.